The present invention relates generally to a smoking article including a filter for selectively removing carbonyl-containing combustion products from main stream smoke and, more particularly, a filter for selectively removing carbonyl-containing combustion products, including at least one carrier having a developed structure including a plurality of moieties capable of the nucleophilic attack of carbonyl-containing combustion products.
Some tobacco combustion products contribute to the organoleptic pleasures, while others detract. Among the combustion products that detract are carbonyls including aldehydes, such as acetaldehyde and acrolein, and ketones, such as acetone. When removing detracting combustion products, current filter technology also removes products that contribute to the positive organoleptic pleasure of a smoker. For example, when removing carbonyl-containing combustion products, flavoring additives are removed. Even without flavoring additives, the tobacco combustion products that contribute to the positive organoleptic pleasure of a smoker are removed resulting in an undesirable tobacco product from the consumer""s perspective. In both examples, the filtering has proven unacceptable.
Thus, there remains a need for a new and improved smoking article that includes a filter element that selectively removes carbonyl-containing combustion products that detract from the organoleptic pleasures of a smoker, while at the same time, it allows the desirable combustion products to reach the smoker.
The present invention is directed to a smoking article, including a wrapper surrounding a tobacco column, a selective filter element including at least one carrier having a developed structure, and a plurality of moieties capable of the nucleophilic attack of carbonyl-containing combustion products. The plurality of moieties of the smoking article are supported by the at least one carrier. At least one additional filter element may be provided to filter other combustion products. Preferably, at least one additional filter element is a cellulose acetate. The developed structure of the at least one carrier encourages the interaction of the carbonyl-containing combustion products and the plurality of moieties capable of the nucleophilic attack.
In an embodiment, a carrier is a polymer, preferably having a large surface area such a branched polymer. Preferred polymers include partially oxidized cellulose and polyaniline. In another embodiment, a carrier is an inorganic oxide, preferably a zeolite. Preferred inorganic oxide include an oxide of aluminum, silicon, aluminum and silicon, and their combinations. In yet another embodiment, a carrier is an activated carbon.
A spacer may be used for attaching a moiety to the carrier. Preferred spacers include a xe2x80x94COxe2x80x94 group, a xe2x80x94COxe2x80x94[CH2]nxe2x80x94COxe2x80x94 group where n has a value from 1 to 4, a xe2x80x94COxe2x80x94[CH2]nxe2x80x94COxe2x80x94 where n has a value greater than 4 and their combinations.
A moieties capable of the nucleophilic attack may include a nitrogen and hydrogen containing group, preferably a primary nitrogen containing group such as an aminoxe2x80x94(e.g., xe2x80x94NH2) and an iminoxe2x80x94(e.g., xe2x80x94HCxe2x95x90NH), preferably a primary amino group. Preferred moieties capable of the nucleophilic attack include, a hydrazidexe2x80x94(e.g., xe2x80x94NHxe2x80x94NH2), a hydrazonexe2x80x94(e.g., xe2x80x94HCxe2x95x90Nxe2x80x94NH2), and a semicarbazidexe2x80x94(e.g., xe2x80x94C(xe2x95x90O)xe2x80x94NH2).
In an embodiment, the selective filter element is a tip added to a smoking article prior to the smoking of the smoking article. The tip may be added by a smoker. Also, a smoking article may further include an additional filter element which is preferably a cellulose acetate filter element.
Accordingly, one aspect of the present invention is to provide a smoking article having a wrapper surrounding a tobacco column and a selective filter element including a plurality of moieties capable of the nucleophilic attack of carbonyl-containing combustion products of the smoking article. Also contemplated is a method for making, a method of operation of and a product resulting from using a smoking article.
Another aspect of the present invention is to provide a selective filter element for use in a smoking article including a wrapper surrounding a tobacco column, the selective filter element having at least one carrier having a developed structure, and a plurality of moieties capable of the nucleophilic attack of carbonyl-containing combustion products of the smoking article supported by the at least one carrier. The developed structure of the at least one carrier encourages the interaction of the carbonyl-containing combustion products and the plurality of moieties capable of the nucleophilic attack. Also contemplated is a method of making, a method of operation of and a product resulting from using a selective filter element.
Still another aspect of the present invention is to provide the smoking article including a wrapper surrounding a tobacco column, a selective filter element including at least one carrier having a developed structure, and a plurality of moieties capable of the nucleophilic attack of carbonyl-containing combustion products of the smoking article supported by the at least one carrier and at least one additional filter element. The developed structure of the at least one carrier encourages the interaction of the carbonyl-containing combustion products and the plurality of moieties capable of the nucleophilic attack. Also contemplated is a method for making, a method of operation of and a product resulting from using a smoking article.
These and other aspects of the present invention will become apparent to those skilled in the art after a reading of the following description of the preferred embodiments, when considered with the drawings.